How to make a hollow cube object?

Question

How to make a hollow cube object by Python?

edges = []
verts = [(1.0, 1, 0), (1.0, -1.0, 0), (-1, -1, 0), (-1, 1, 0),(2.0, 2, 0), (2.0, -2.0, 0), (-2, -2, 0), (-2, 2, 0)]
faces = [(0, 1, 2, 3), (4, 5, 6, 7)]
mesh_data = bpy.data.meshes.new("cube_mesh_data")
mesh_data.from_pydata(verts, [], faces)
mesh_data.update()
hsname='hollowobj'
hsobj = bpy.data.objects.new(hsname, mesh_data)
bpy.context.collection.objects.link(hsobj)
bpy.context.view_layer.objects.active = hsobj
hsobj.select_set(True)
bpy.ops.object.modifier_add(type='SOLIDIFY')
bpy.context.object.modifiers["Solidify"].thickness = 2

But it did not work!

Hello, could you add a diagram or example of what you're trying to construct ? — Gorgious, Jul 07 '21 at 12:12
If Tlousky's answer is not what you're after, then perhaps you just want to create two cubes - the inner cube would be the inner surface - of course you would have to flip the normals of the inner cube. — Markus von Broady, Jul 07 '21 at 13:51

score 7 · Answer 1 · answered Jul 07 '21 at 12:52

You can use the bmesh create_cone operator to generate a hollowed out tube (essentially a 4 sided cylinder).

import bpy, bmesh
bm = bmesh.new()
bmesh.ops.create_cone(
    bm, cap_ends=False, cap_tris=False, 
    segments=4, diameter1=1, diameter2=1, depth=2
)
name = 'Hollow Cube'
m = bpy.data.meshes.new(name)
C = bpy.context
S = bpy.context.scene
bm.to_mesh(m)
o = bpy.data.objects.new(name, m)
S.collection.objects.link(o)

You can later add a solidify modifier like you did (or by using the more efficient low-level object.modifiers.new method.

batFINGER · Answer 2 · 2021-07-07T14:16:53.217

Reverse Engineer it.

In answers to

How to draw a circle hole by bmesh on the plane?

and

and Create Circle with Inner Radius (Similarly to @Tlouskey mentions adding a cone, but whereas he is using solidify thickness for wall thickness, cone with depth=0 and hence solidify thickness as height if you will

demonstrate other methods to make a hole in a mesh object.

another would be add plane, inset face, then delete face.

Reminder start with cursor in sensible position, anyway set inset to 1

which could be coded, however and having just done that, will use How do I Create a script for geometry I create? to "reverse engineer it into a script"

import bpy
context = bpy.context
verts = ((-2.0, -2.0, 0.0),
         (2.0, -2.0, 0.0),
         (-2.0, 2.0, 0.0),
         (2.0, 2.0, 0.0),
         (-1.0, 1.0, 0.0),
         (-1.0, -1.0, 0.0),
         (1.0, -1.0, 0.0),
         (1.0, 1.0, 0.0))
faces = ((5, 4, 2, 0),
         (6, 5, 0, 1),
         (7, 6, 1, 3),
         (4, 7, 3, 2))
me = bpy.data.meshes.new("Plane")
me.from_pydata(verts, [], faces)
ob = bpy.data.objects.new("Plane", me)
context.collection.objects.link(ob)
context.view_layer.objects.active = ob

edit to change "Plane" to suit, and as mentioned can add modifier by appending

sm = ob.modifiers.new("Solidify", 'SOLIDIFY')
sm.thickness = 2

to script.

Note.

To make the cube hollow by giving it "wall thickness", can add the modifier directly to the default cube.

A sphere is used via boolean difference modifier for cutaway.

Thanks! It worked very well! – Derekcbr Jul 08 '21 at 23:27 — Derekcbr, Jul 08 '21 at 23:27

How to make a hollow cube object?

2 Answers2